Articles

Digisight LRF. Night vision riflescope with range finder

Two in one. In all spheres and in all times attempts have been made often very successful to combine two or more things often used for solving parallel challenges in one.

October 16 2014

Author: Alexander Boyko

Source:
Safari Magazine (Russia), #9'2014

Picture
Alexander Boyko

In familiar to us hunting subject area most often reminded examples are connected with day optics. Riflescopes and binoculars with rangefinders, ballistic calculators, compasses… Even the image stabilizer in the binocular can be considered as a high-tech alternative to a tripod.

In the field of night optics examples of successful combination can be counted on the fingers of one hand. They are mainly realized in the devices with digital “converters” (night vision devices and thermal cameras) and mainly in the form of integrated video recording units.

Digisight LRF is perhaps the first existing not only in the internet but in the reality night vision riflescope with integrated laser ranger finder.

In night conditions distances are perceived in a different way comparing to daytime. In well-known places where all distances had been measured many times there is no need in a range finder (though, I have not met any night time range finders before either). If the place is unfamiliar and the animals can appear at distances where bullet’s ballistic behavior already matters, then precise range estimation for the shot will be synonymous to a correct hit.

In Digisight LRF N850 range finder is made in the shape of additional unit on the left side of the body (if we take a working position – facing the eyepiece). Emitter and receiver of range finding module are separated from the optic channel. Claimed range of measurement makes up 400 m precision ±1 m. Range finder is activated by pressing the button on the body of the scope (large button on top) or on the remote control, at this point the reticle disappears while the mark of the range finder (its configuration can be changed) appears on the screen. Range measurement is performed by the second pressing of the button. Measurement result (meters/yards) is displayed in the top right corner of the screen. In 3 seconds reticle appears on the screen again (measurement results disappear) Digisight LRF is ready for shooting. Besides the single measurements there is a possibility of scanning – range information changes during the movement of the riflescope from object to object in real-time mode. In the conditions of variable relief, during shooting from high stands it is wise to use THD (true horizontal distance) function, its main meaning is that the range finder takes into account the angle of the shooter’s position against the target (its value is also displayed) and shows real horizontal distance to an object. When making corrections this value is the one that has to be considered.

Possessing a new for night vision riflescopes peculiarity, Digisight LRF N850 did not appear from scratch – significant part of construction decisions, optic part and functional abilities is borrowed from the late models of the “N700-th” series.

First of all a significant amount of preloaded reticles, 13 configurations, and each reticle has 4 options of color combination of its elements: illumination area (central as a rule) can be red or green, main part can be black or white. Considering configuration there are simple reticles and graded, reticles for firearms, airguns and crossbow. Digisight LRF N850 can store up to 3 positions of zeroing in the memory for different distances, weapons (if the riflescope is used simultaneously on different weapons) or ammunition.

The most difficult during the testing was making photos through the eyepiece. The images show the screen in the modes of distance measurement and observation (aiming). Objective cover is closed.

At this point functional novelties can be called significant. With basic optic magnification 4,5 times Digisight LRF also has continuous (10 steps) zoom up to 9 times (in the previous models digital zoom was also present, but magnification changed from 4,5 to 7 without any intermediary steps). One shot zeroing function has been upgraded with a useful feature – now after the shot it is possible to “freeze” the image of the target on the screen and match the reticle with POI without maintaining immobility of weapon and riflescope.

A new option – indication of a side tilt of a weapon: during a side tilt for more than 5 degrees a warning sign appears on the screen – arrows that show the direction of the tilt and graphic rendering of tilt extent (Digisight does not show numerical information about side tilt).

In certain circumstances automatic switch off function can be useful (it can be activated in the menu). It works in the following way - if the weapon retains not characteristic for shooting position (70° vertical incline and 30° horizontal incline to any side) in the course of 10 seconds and more, the riflescope will be switched off. For the same purpose – battery life saving – the riflescope has the possibility of switching the video output off if it is not used.

In the part of visible image adjustments they added the possibility to change the brightness of the overlay display graphics. Judging by experience of work with Digisight N750 we can say that the function of saving user’s brightness and contrast settings as well as the possibility to return to factory settings suggest itself. Both of those functions are implemented. A big advantage is that when making a return to factory settings the zeroing of the scope is not reset. It is definitely worth noticing the controls which have been simplified proportionally to the expansion of the functionality. That is very significantly.

Activation of the scope and IR illuminator is done by a five position switch (Off, On plus three positions of IR illuminator power level).

Apart from the switch there are 2 buttons, encoder- wheel and focusing wheel on the body of the scope. The range finder button has been mentioned before. The second button is adjusted – the hunter can select its function independently choosing from several options. By default the button activates the function of sensor’s sensitivity boost, though I assigned reticle color change to this button straight away. The rest of the controls are performed with the help of a large encoder (wheel that can be both rotated and pushed). There is also a wireless remote control that backs up the most essential functions – turning ON/OFF, controlling IR illuminator and integrated range finder.

Testing has been done in night time and day time conditions on a carbine Steyr Mannlicher, with 30-06 Sprg. ammunition.

The riflescope has demonstrated an accurate controllability – placement of buttons, switch, wheels and their design does not cause any complaints. Buttons have a large diameter (14-17mm) they are marked by beads – it is very easy to locate the button and push it in the complete darkness.

I was more interested in shooting targets at different distances. On the shooting range 10 targets were placed in random order. Before the shot the shooter was measuring distance to selected target, then he was shooting making corrections on one of the available mildot-shaped reticles after that the target was out of round. In the result all impact points hit higher than “8” which can be regarded as a very decent result considering the fact that the closest target was situated at the distance of 40 m and the most distant at 320 m. The maximal measuring result to assistant’s figure in the night made up 420 m.

Digisight LRF has demonstrated its reliability both as a night vision riflescope and as a range finder. Again and again I want to mention clever controls implementation: auxiliary and secondary functions such as clock setting, video out format selection, zeroing etc. are hidden deep in the menu whereas the main functions necessary for real hunting conditions are activated by a motion of a finger.

There have been many arguments over what is best for night observation. The difference between the technologies, approaches and the large number of models used today has created a choice that could not have been imagined even several years ago.

Two lines of innovative, high resolution thermal imaging monoculars and riflescopes, respectively the Helion and Trail, have been introduced by Pulsar. Both optics integrate ground breaking features and functions.